University of Minnesota

“If It Isn’t Fun.” – Part 10 – The National Diet-Heart Study

The National Diet-Heart Pilot Study during the 1960s explored the feasibility of a multi-center project to recruit and maintain subjects on prescribed cholesterol-lowering diets. The investigators in five centers came from varied disciplines in studies of the causes of atherosclerosis, each a pioneer in his or her field, but eventually rather uncomfortable bed-fellows.

Minnesota was strongly represented in “Diet-Heart” by Ancel Keys, who had made fundamental contributions, including the Keys Equation, which was, and is, the best quantitative expression of the effects on blood cholesterol level of changes in diet fats and cholesterol. He and the LPH had a long experience in organizing and conducting controlled trials, and had recently organized extensive surveys of the U.S. Railway and Seven Countries Study. Keys represented the broad vision and the multiple skills and disciplines needed at this early day of research into the causes and prevention of heart attacks. He, Henry Taylor, and Paco Grande participated actively in the national design for the double-blinded diet segment of the trial but also proposed and carried out a segment they considered more relevant to real needs. That was a study of subject education about eating patterns and their purchase and preparation of foods from the open market.

Heavily involved at the time with Seven Countries field work, I participated only in the medical procedures for evaluation of the trial participants, but learned much by exposure to the intense Minnesota activities in the study, including design and sample size computations for randomized trials, which would come in handy later.

Much of the legwork in this trial locally was put in the hands of an old Harvard colleague of Keys and Taylor, Stanton Fetcher, who took early retirement from ranching to join the staff. Nedra Foster, our many-talented administrative assistant, nutritionist, and technician was the study glue. Together they developed an efficient diet-heart clinic in rented quarters above Stub and Herb’s bar at Oak and Washington on campus. Joe Anderson ran the clinic’s blood lipid laboratory and participated in standardization established by CDC for central quality control for the trial and for others over many decades to follow. Heart Disease Control Program officers were assigned to us and Minnesota flourished as part of the national grouping of centers prepared to direct an eventual “definitive study” of diet-heart issues, which was confidently anticipated by all the investigators.

A separate Minnesota segment under Ivan Frantz and Patricia Ashman, carried out double-blinded diet trials in Minnesota mental hospitals and developed advanced laboratory methods. Benjamin Baker and Ed Murphy directed the Baltimore clinic, Larry Kinsell in Oakland, Jerry Stamler, Dave Berkson, and Yolanda Hall at Chicago, and Fred Stare, Bob McGandy and Mark Hegsted at Harvard, led their respective centers in the double-blind trial segments. A national center prepared food products with special composition designed to maintain or lower blood lipids. Each center ran a commissary to supply these at low cost to participants, whose diet patterns and blood lipid measurements were subsequently monitored. Jerry Cornfield and Fred Ederer made the data analyses in Bethesda, Gerald Cooper set up his soon-to-be-famous Central Lipid Laboratory in Atlanta, and the grandfather of atherosclerosis research himself, Irvine Page, of the Cleveland Clinic, chaired the Executive Committee of this fine organization.

The Diet-Heart investigators prepared a thoroughgoing report of the trial and concluded that both blinded and non-blinded strategies were feasible and effective for lipid lowering over a substantial period of time.* They recommended a definitive, long-term, large-scale trial to examine the effect of diet and other means in reducing heart attack incidence, and the formation of a committee to develop plans and protocol.

Then the public debate and the agonizing began.

Nationally, there was a contingent among scientists and clinicians that found the evidence from clinical, laboratory, and population studies congruent and already sufficient unto itself to justify public health policy and action for the prevention of CVD by dietary means. Among a larger segment of the scientific community, there was, however, the view that a randomized clinical trial of diet and disease risk was essential before far-reaching diet changes should be proposed for the public health.

A “Blue Ribbon” Panel, presumably representing both these views, was commissioned by NIH to make recommendations about the definitive Diet-Heart Trial. It came to be known by the name of its chairperson, the Ahrens’ Committee. After long and quite tortured deliberations it reported out, concluding that the sample size requirements, and consequent national research apparatus and expert staffing and costs, exceeded any feasible trial strategy. More serious than its negative conclusion, which was based on the smaller thinking and budgets of that day rather than on actual feasibility and cost in the face of the rampant national epidemic, was the subsequent dilemma and delay of NIH in arriving at any constructive research strategy for CVD prevention.

The Makarska Conference (see below), and new NIH and WHO task force deliberations in the early ’70s provided the plans that were finally implemented some five years after the Diet-Heart Study Report. A new, forward NIH strategy and policy for trials of blood pressure and cholesterol lowering, and for smoking cessation, or for all combined, finally got underway in 1972, just at the time I became director of the LPH on Keys’s retirement.

Timing, they say, is everything.

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